Present-day skis generally have a composite structure in which different materials are combined in such a way that each of them comes optimally into play, given the distribution of the mechanical stresses. Thus, the structure generally comprises peripheral protective elements forming the upper and lateral surfaces of the ski and internal resistance elements, or strips, made of a material having great mechanical strength and rigidity. The structure also comprises filling elements such as a central core embodying a cellular structure, a sliding sole plate which forms the lower surface of the ski and allows the ski to slide properly on the snow, and lower metal squares forming the lower ribs of the ski.
To obtain the appropriate physical characteristics, the manufacture of modern skis thus requires the assembly of a relatively large number of elements made of different materials, which must be bonded or welded to each other to produce the final ski structure.
In injection techniques used for ski manufacture, one of the major difficulties lies in the positioning and position maintenance of the ski components in the mold before injection.
Techniques have been proposed to form several sub-assemblies before molding, each of which is obtained by joining several elements together. However, these techniques increase the number of successive operations.
In addition, in conventional techniques, it appears difficult to produce external ski surfaces whose dimensions are very precise.